Inspection system for limited access spaces

ABSTRACT

A limited access space inspection system comprising: a sensing device for carrying out sensing over a region in the limited access space, a mounting for mounting the sensing device to scan about the limited access space and a scanning control unit, associated with the sensing device, for controlling the sensing device to scan about the limited access space. The device is particularly useful for improving by automation, security checks, customs checks and safety checks involving such awkward to access spaces. The sensing device may be an imaging device, or a sensor for detecting traces of chemical substances.

RELATED PATENT APPLICATION

This application is a National Phase Application of PCT/1L03/00754having International Filing Date of 18 Sep. 2003, which claims priorityfrom U.S. patent application Ser. No. 10/252,040 filed 23 Sep. 2002.

FIELD AND BACKGROUND OF THE INVENTION

The present invention relates to an inspection system for limited accessspaces and, more particularly, but not exclusively to a vehicleinspection system suitable for inspection of parts of vehicles that areawkward to inspect easily.

Vehicle underside inspection is necessary for several reasons, one beingto provide security, a second being for safety and a third being forcontraband detection, by customs inspectors and the like. On thesecurity side, undersides of vehicles may have concealed explosivedevices. Of particular concern is the possibility of concealing anexplosive device on the underside of a fuel tanker, which device istimed or controlled to explode when the tanker is inside a fueldistribution depot. Carrying out detailed manual inspections of theundersides of each tanker entering a fuel depot is both time and laborconsuming. On the safety side, the underside of the vehicle may conceala mechanical flaw, the early detection of which may prevent an accident.In a garage or workshop a car is generally jacked up or placed on aramp. Larger vehicles are placed on ramps or are driven over inspectionpits. However, outside the garage environment, inspection of theunderside of a vehicle is difficult. Contraband detection at borders bycustoms officials is often based on spot checks since customs veryrarely have the resources to inspect every passing vehicle. Any means ofallowing a more detailed inspection in a smaller time frame would bewelcome.

Security checks for entry into government buildings and the like aretypically carried out using a mirror on the end of a pole, which isinserted under the vehicle. However, without illumination it isdifficult to see much detail and even with illumination, an explosivedevice can be concealed in a spot that is awkward to view using themirror. Furthermore such a mirror is very unlikely to spot hairlinecracks, which are usually the first signs of dangerous mechanicalfaults. It is impractical to install inspection pits at all places whereregular vehicle checks are desirable.

U.S. Pat. No. 6,249,567 to Rothschild et al discloses an inspectionsystem for inspecting a vehicle moving at a grade of travel over asurface and for detecting material disposed within or on the undersideof the vehicle. The system has a source for providing a generally upwardor downward pointing beam of penetrating radiation of specifiedcross-section so as to illuminate vehicles driven above or below thesource of radiation. A detector arrangement, disposed below the grade oftravel, detects radiation from the beam scattered by any materialdisposed on the underside of the moving vehicle and generates ascattered radiation signal that may be used for characterizing thematerial disposed on the underside of the vehicle. Similarly, a detectorarrangement disposed above the vehicle generates a scattered radiationsignal that may be used for characterizing the material disposed withinthe vehicle. The system however sits at a single location, requiring thevehicle to move during inspection. It cannot independently scan thevehicle underside. Furthermore, the main detection function of thesystem is based on x-rays, since a principle intention is to scan forthe internal contents of the vehicle.

There is thus a widely recognized need for, and it would be highlyadvantageous to have, a vehicle inspection system devoid of the abovelimitations.

SUMMARY OF THE INVENTION

According to one aspect of the present invention there is provided alimited access space inspection system comprising:

-   a sensing device for sensing within a region in the limited access    space,-   a mounting for mounting the sensing device to be scannable about the    limited access space and-   a scanning control unit, associated with the sensing device, for    controlling the sensing device to scan about the limited access    space.

The sensing device may be an imaging device or a trace sensing devicesuch as a sniffing device or spectroscopy-based device.

The system preferably comprises a protective housing for protecting theimaging device from the environment by interposing between at least theimaging device and the region to be imaged.

Preferably, the protective housing comprises a transparent regionlocated between the imaging device and the region to be imaged.

Preferably, the transparent region comprises laminated glass.

Preferably, the laminated glass is triplex laminated glass.

Preferably, the mounting is a floor mounting for mounting the imagingdevice at floor level.

Preferably, the mounting comprises a camera track for movably bearingthe imaging device.

Preferably, the mounting comprises guide tracks for guiding a vehiclethereover, an underside of the vehicle thereby forming the limitedaccess space.

Preferably, the mounting is a flush floor mounting for insertion into afloor cavity.

The system preferably comprises an illumination source for providingillumination to the limited access space.

The system preferably comprises a display output for providing a displaysignal.

Preferably, an image processor is located between the imaging device andthe display output to process images from the imaging device prior tooutput.

Preferably, the image processor is operable to compare a current imageof the region with a previous image to detect differences therebetween.

Preferably, the imaging device is linearly movable along the cameratrack, is rotatable about an axis perpendicular to the track, and isfurther rotatable about an axis parallel to the track.

Preferably, the scanning control unit is controllable by at least one ofdirect user input and by preprogramming, to scan the imaging deviceabout the limited access space.

In one embodiment the inspection system is mounted on a mobile trailer.

According to a second aspect of the present invention there is provideda vehicle underside inspection system comprising:

-   a floor mounted track,-   an imaging device mounted on the floor track to be linearly movable    along the floor track, and-   a display output, associated with the imaging device, for providing    a display signal of output of the imaging device.

The system preferably comprises a scanning controller for controllingthe imaging device to scan an imaging region over the floor track.

Preferably, the imaging device is rotatable about an axis perpendicularto the floor track, and is further rotatable about an axis parallel tothe floor track.

Preferably, the floor mounted track comprises an outer housing andwherein the imaging device is sealed within the outer housing.

According to a third aspect of the present invention there is provided amethod of scanning a limited access space, the method comprising:

-   interpolating a linear track into the space, the linear track having    an imaging device movably mounted thereon, and-   moving the imaging device along the track, thereby to scan the    space.

Preferably, the interpolating the linear track into the space compriseslocating a vehicle over the track, an underside of the vehicle formingthe limited access space.

The method preferably further comprises interpolating an illuminationsource into the space.

Preferably, the linear track is flush with a floor.

Unless otherwise defined, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which this invention belongs. The materials, methods, andexamples provided herein are illustrative only and not intended to belimiting.

Implementation of the method and system of the present inventioninvolves performing or completing certain selected tasks or steps suchas scanning manually, automatically, or a combination thereof. Moreover,according to actual instrumentation and equipment of preferredembodiments of the method and system of the present invention, severalselected steps could be implemented by hardware or by software on anyoperating system of any firmware or a combination thereof. For example,as hardware, selected steps of the invention could be implemented as achip or a circuit. As software, selected steps of the invention could beimplemented as a plurality of software instructions being executed by acomputer using any suitable operating system. In any case, selectedsteps of the method and system of the invention could be described asbeing performed by a data processor, such as a computing platform forexecuting a plurality of instructions.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is herein described, by way of example only, withreference to the accompanying drawings. With specific reference now tothe drawings in detail, it is stressed that the particulars shown are byway of example and for purposes of illustrative discussion of thepreferred embodiments of the present invention only, and are presentedin the cause of providing what is believed to be the most useful andreadily understood description of the principles and conceptual aspectsof the invention. In this regard, no attempt is made to show structuraldetails of the invention in more detail than is necessary for afundamental understanding of the invention, the description taken withthe drawings making apparent to those skilled in the art how the severalforms of the invention may be embodied in practice.

In the drawings:

FIG. 1 is a simplified diagram showing a vehicle underside inspectionsystem according to a first preferred embodiment of the presentinvention;

FIG. 2 is a simplified block diagram showing electronic subsystems ofthe vehicle underside inspection system of FIG. 1;

FIG. 3 is a simplified cross section of the vehicle underside inspectionsystem of FIG. 1;

FIG. 4 is a flow chart showing a first embodiment of operation of thesystem of FIG. 1:

FIG. 5 is a flow chart showing a second embodiment of operation of thesystem of FIG. 1,

FIG. 6 is a schematic diagram showing assembly details of a prototypeembodiment of the present invention viewed from the side,

FIG. 7 is a schematic diagram showing assembly details of the sameprototype as viewed along the direction of the track,

FIG. 8 is a schematic diagram illustrating a further embodiment of thepresent invention having lighting tracks on either side of the cameratrack,

FIG. 9 is a schematic diagram illustrating a mobile trailer for mountingan inspection assembly in order to provide a mobile embodiment of thepresent invention,

FIG. 10 is a schematic diagram illustrating an inspection assembly formounting on the trailer of FIG. 9,

FIG. 11 is a schematic diagram illustrating the inspection assembly ofFIG. 10 mounted on the mobile assembly of FIG. 9, and

FIG. 12 is a view from above of the assembled mobile inspectionassembly.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present embodiments comprise a controllably movable imaging devicemounted on a camera track. The track may be floor mounted to allowvehicles to be driven over it and may further include an illuminationsource. The floor mounting may for example be part of an inspection pit,or part of a ramp or part of a mobile inspection assembly, as will bedescribed herein. The imaging device, preferably a still or videocamera, may be scanned along a vehicle underside as an operator viewsthe resulting images on a screen. The imaging device is preferablysealed under laminated glass to protect from environmental hazards. Thecamera track may be mounted between vehicle guide tracks.

The principles and operation of a controllably movable imaging devicemounted on a camera track according to the present invention may bebetter understood with reference to the drawings and accompanyingdescription.

Before explaining at least one embodiment of the invention in detail, itis to be understood that the invention is not limited in its applicationto the details of construction and the arrangement of the components setforth in the following description or illustrated in the drawings. Theinvention is capable of other embodiments or of being practiced orcarried out in various ways. Also, it is to be understood that thephraseology and terminology employed herein is for the purpose ofdescription and should not be regarded as limiting.

Referring now to the drawings, FIG. 1 illustrates a limited access spaceinspection system. The inspection system 10 comprises an imaging device12 for imaging a region in the limited access space. The imaging device12 is mounted on a track 14 within a track mounting 16. The imagingdevice 12 is linearly movable along the track 14 in the direction ofarrow 18 and is preferably also able to rotate about the track and aboutan axis perpendicular to the track, the latter at 360°, with the help ofcontrollable actuators. In a preferred embodiment the imaging device isa dome-mounted camera system, such as the Sivis Mini Dome System 3marketed by Siemens GmbH of Munich, Germany. Such a dome systemautomatically provides numerous camera movement features such asrotation, tilt, pan, zoom-in, zoom-out and the like and is fullyprogrammable.

The camera is preferably a standard black and white or color still orvideo camera. In a preferred embodiment the camera is able to alternatebetween black and white and color modes. Alternatively, depending onwhat the system is being used to monitor, infra-red, ultra-violet orx-ray or other radiation detectors may be used. For specializedapplications such as field use by the military, the camera may be anykind of night vision camera, such as an infra-red camera or an active orpassive device based on an image intensifier. Spectrometers and otherspectral imaging devices may also be used. Spectrum-based imaging isuseful for identifying substances such as explosives.

As an alternative to image detectors, it is possible to use sensingdevices that scan for traces of chemical substance. Such devices includesniffing devices, which are able to detect extremely low concentrationsof substance. As well as sniffing devices, laser based spectrometers canbe used. An example of a laser based spectrometer that can be used isthe portable aerosol beam-focused laser-induced plasma spectrometerdescribed at http://www.epa.gov/ttn/emc/meetnw/harre.pdf, the contentsof which are hereby incorporated by reference in their entirety. Thedevice is described in relation to the detection of metals, but issuitable for other substances such as the nitro-type substances likelyto be found in explosives. Another suitable device which can be used inconjunction with the present invention, is that disclosed athttp://www.hud.ac.uk/schools/applied_sciences/chem/TDLGroup/freibpap.htm,the contents of which are hereby incorporated by reference.

The track mounting 16 is preferably located between vehicle guide tracks20, to allow a vehicle to position itself above the imaging device 12.The track mounting is preferably designed to be inserted into the floorso that a vehicle simply has to drive onto the vehicle guide tracks toprovide the imaging device with a clear view of the underside of thevehicle.

Reference is now made to FIG. 2, which is a simplified block diagramshowing the various electronic subsystems of the inspection system ofFIG. 1. An imaging subsystem 22 comprises a camera or other imagingdevice and associated imaging electronics. A scanning subsystem 24comprises a scanning control subsystem 26 and an actuation subsystem 28.The actuation subsystem moves the camera through linear and rotarymotion in accordance with instructions from the scanning controlsubsystem. The scanning control subsystem controls the camera to scanthe vehicle underside, either according to a pre-recorded program oraccording to instructions received from the user or operator as he viewsthe output on a screen.

An image processing subsystem 30 carries out various image-processingoperations additional to those that a typical camera may normallyprovide. For example it may increase contrasts, use an overall lightinglevel to select between color and black and white modes, and in aparticularly preferred embodiment may carry out alignment between acurrent image and a stored image and then carry out a comparison inorder to detect differences between the two images. Such a comparison isuseful for mechanical inspections of the same vehicle. That is to say aninspection of a given vehicle may be compared with an earlier inspectionof the same vehicle so as to detect the appearance of cracks or thedevelopment of existing cracks. In automated security comparison may bemade with a stored image of the same type of vehicle so as to highlightobvious differences such as the insertion of an explosive device.

A viewing subsystem 32 takes output either directly from the imagingsubsystem 22 or from the image processing subsystem 30 and displays it.The viewing subsystem 22 may use any kind of visual display unit. Anillumination subsystem 34 preferably comprises a light or otherillumination source, which preferably moves along with the imagingdevice 12. If a radiation detector for radiation other than light isused then the illumination source is selected accordingly.

Reference is now made to FIG. 3, which is a simplified cross-section ofthe track mounting 16 of FIG. 1. Track mounting 16 comprises a base 40upon which is mounted camera track 14. Camera track 14 may be toothedalong its length to improve traction and accuracy of the actuationsystem. The imaging device 12 is preferably mounted within a domeconstruction 42, as described above. Track mounting 16 further comprisesa protective housing 44 for protecting the imaging device from theenvironment. The protective housing preferably seals the imaging deviceand supporting electronics from the external environment. At the veryleast the protective housing interposes between the imaging device andthe region to be imaged, thus protecting the imaging device from oilspillage, knocks and other hazards.

Preferably, the protective housing comprises a transparent regionlocated between the imaging device and the region to be imaged. In anembodiment, the transparent region comprises laminated glass, and in aprototype triplex laminated glass of 22 mm thickness was used.

Preferably, the mounting is a floor mounting for mounting the imagingdevice at floor level. In a particularly preferred embodiment, themounting is a flush floor mounting for insertion into a floor cavity.

Reference is now made to FIG. 4, which is a simplified flow chartshowing operation of a preferred embodiment of the present invention. InFIG. 4 a vehicle is driven onto a rail carrying an imaging device. Theinvention is not however restricted to “drive-on” inspection of vehiclesand thus, as an alternative, it is possible to insert a rail carrying animaging assembly into any kind of space that it is difficult to accessand then to operative the assembly to scan the space. In either case,the imaging device then scans the space, either under control of aprogram or according to instructions from an operator. The output isviewed and the operator decides whether any kind of action is necessary.The output may additionally be recorded if desired.

Reference is now made to FIG. 5, which is a flow chart showing operationaccording to an alternative embodiment of the present invention. Stagesthat are identical to those of FIG. 4 are not described again except asnecessary for an understanding of the present embodiment. In FIG. 5 thepositioning and scanning stages are the same. However at that point aprevious scan of the same vehicle or same kind of vehicle is retrievedif available and a comparison is carried out between the two scans. Theoperator is then alerted regarding any differences.

Reference is now made to FIG. 6, which is a simplified schematic diagramshowing assembly details of a prototype embodiment of part of aninspection system according to the present invention viewed from theside. Reference is simultaneously made to FIG. 7 which shows the sameassembly viewed along the direction of the rail. Parts that are the sameas in previous figures are given the same reference numerals and are notdescribed again except to the extent necessary for an understanding ofthe present figure. The dome construction 42 is located on track 14which itself is located on track mounting 16. A motor 50 is providedalongside the dome construction 42 to provide the dome construction withtraction to run along the track 14. The motor 50 powers toothed pulleys52, which intermesh with a toothed central runway of the track 14,thereby to provide the traction.

Reference is now made to FIG. 8, which is similar to FIG. 1. Parts thatare the same as in FIG. 1 are given the same reference numerals and arenot referred to again except as necessitated for an understanding of thepresent embodiment. FIG. 8 differs from FIG. 1 in that it includes abuilt in lighting track 60 on either side of the camera track 14. Thelighting track 60 preferably comprises fluorescent tubes 62.

Reference is now made to FIGS. 9-12, which are simplified diagramsshowing a further preferred embodiment of the present invention. Theembodiment shown in FIGS. 6 and 7 is intended for mounting inside aninspection pit or under a ramp as a permanent fixing. However there isalso a need for a mobile version. The mobile version may be used as ademonstrator or it may be used for providing temporary or short termsecurity. FIG. 9 shows a mobile trailer 80 comprising a platform 82, acoupling assembly 84 for attaching to a motorized vehicle for traction,wheels 86 and extendible legs 88. The trailer also has pivotable rampmembers 90 to allow an inspection assembly to be raised onto thetrailer.

FIG. 10 shows an inspection assembly 100 which is suitable for mountingon trailer 80. The inspection assembly 100 comprises pivotable rampmembers 102 on either side at front and back. The ramp members arefolded for transport and opened out to provide a ramp to allow vehiclesto mount the assembly.

Track members 104 link forward and rear ramp members over centralsection 106 of the assembly. The track members provide a track for avehicle to pass over and stop over the central section. Between the twotrack members 104 is an inspection hollow 108 in which the camera andcamera track may be mounted within protective housing 44. The content ofthe inspection hollow is preferably as described in the previousembodiment. The track members 104 are raised on supports 110 so as toprovide the vertical space needed for the inspection hollow to be ableto accommodate the camera and track.

FIG. 11 is a schematic view showing the mobile trailer 80 with theinspection assembly mounted thereon. Parts that are the same as inprevious figures are given the same reference numerals and are notdescribed again, except as necessary for an understanding of the presentfigure. In FIG. 10, the assembly ramp members 102 are shown folded overthe track members 104, ready for travel.

FIG. 12 is a schematic view from above showing the assembly 100 mountedon trailer 80. Again the ramp members are folded. The camera track 14,and camera mounting 12, are seen in the inspection hollow 108, flankedon either side by lighting tracks 60.

It is expected that during the life of this patent many relevant imagingdevices and systems will be developed and the scope of the terms herein,particularly of the terms “camera” and “imaging system”, is intended toinclude all such new technologies a priori.

Additional objects, advantages, and novel features of the presentinvention will become apparent to one ordinarily skilled in the art uponexamination of the following examples, which are not intended to belimiting. Additionally, each of the various embodiments and aspects ofthe present invention as delineated hereinabove and as claimed in theclaims section below finds experimental support in the followingexamples.

It is appreciated that certain features of the invention, which are, forclarity, described in the context of separate embodiments, may also beprovided in combination in a single embodiment. Conversely, variousfeatures of the invention, which are, for brevity, described in thecontext of a single embodiment, may also be provided separately or inany suitable subcombination.

Although the invention has been described in conjunction with specificembodiments thereof, it is evident that many alternatives, modificationsand variations will be apparent to those skilled in the art.Accordingly, it is intended to embrace all such alternatives,modifications and variations that fall within the spirit and broad scopeof the appended claims. All publications, patents and patentapplications mentioned in this specification are herein incorporated intheir entirety by reference into the specification, to the same extentas if each individual publication, patent or patent application wasspecifically and individually indicated to be incorporated herein byreference. In addition, citation or identification of any reference inthis application shall not be construed as an admission that suchreference is available as prior art to the present invention.

1. A limited access space inspection system for inspecting by scanninginstances of a predetermined set of defined limited access spaces, thesystem comprising: a sensing device configured for scannably sensingover a region in said limited access space, a mounting for mounting saidsensing device to be scannable about said limited access space and ascanning control unit, associated with said sensing device, forcontrolling said sensing device to scan about said limited access spaceaccording to a pre-recorded program, said program selectable for saidinstance within said set and comprising instructions for moving saidsensing device linearly along a track, for rotating said sensing deviceabout an axis perpendicular to said track, and for rotating said sensingdevice about an axis parallel to said track, thereby to configure saidscan for said instance.
 2. The system of claim 1, wherein said sensingdevice is an imaging device.
 3. The system of claim 2, wherein saidimaging device is any one of a group of devices comprising an opticalimaging device, a video camera, an image intensifier, an x-ray imager, aspectrometer, an ultra-violet imager and an infra-red imager.
 4. Thesystem of claim 2, further comprising a protective housing forprotecting said imaging device from the environment by interposingbetween at least said imaging device and said region to be imaged. 5.The system of claim 2, further comprising an illumination source forproviding illumination to said limited access space.
 6. The system ofclaim 2, further comprising an image processor, located between saidimaging device and a display output, to process images from said imagingdevice prior to output for display.
 7. The system of claim 6, whereinsaid image processor is operable to compare a current image of saidregion with a previous image to detect differences therebetween.
 8. Thesystem of claim 1, wherein said sensing device is a trace sensing devicefor sensing traces of the presence of predefined chemical substances. 9.The system of claim 8, wherein said trace sensing device is a sniffingdevice for detecting chemical signatures of said predefined substances.10. The system of claim 8, wherein said trace sensing device is aspectrometer.
 11. The system of claim 10, wherein said spectrometer is alaser spectrometer.
 12. The system of claim 1, wherein said protectivehousing comprises a transparent region located between said sensingdevice and said region to be imaged.
 13. The system of claim 12, whereinsaid transparent region comprises laminated glass.
 14. The system ofclaim 13, wherein said laminated glass is triplex laminated glass. 15.The system of claim 1, wherein said mounting is a floor mounting formounting said sensing device at floor level.
 16. The system of claim 15,wherein said mounting is a flush floor mounting for insertion into afloor cavity.
 17. The system of claim 1, wherein said mounting comprisesa camera track for movably bearing said sensing device.
 18. The systemof claim 17, wherein said sensing device is linearly movable along saidcamera track, is rotatable about an axis perpendicular to said track,and is further rotatable about an axis parallel to said track.
 19. Thesystem of claim 18, wherein said scanning control unit is controllableby at least one of direct user input and by preprogramming, to scan saidsensing device about said limited access space.
 20. The system of claim1, wherein said mounting comprises guide tracks for guiding a vehiclethereover, an underside of said vehicle thereby forming said limitedaccess space.
 21. The system of claim 1, further comprising a displayoutput for providing a display signal.
 22. The system of claim 1,wherein said mounting is located on a mobile unit.
 23. A vehicleunderside inspection system comprising: a floor mounted track, a sensingdevice mounted on said floor track to be linearly movable along saidfloor track, a scanning control Unit, associated with said sensingdevice, configured to control said sensing device to sense about thevehicle underside according to a pre-recorded program, said programbeing variable between vehicle type, comprising instructions for movingsaid sensing device linearly along a track, for rotating said sensingdevice about an axis perpendicular to said track, and for rotating saidsensing device about an axis parallel to said track, said programthereby configuring said scan for specific vehicle type, and an output,associated with said sensing device, for providing a display signal ofoutput of said sensing device.
 24. The system of claim 23, wherein saidsensing device is an imaging device.
 25. The system of claim 24, whereinsaid imaging device is any one of a group comprising an optical imagingdevice, a video camera, an infra-red imaging device, an ultra-violetimaging device, a spectrometer and an x-ray imaging device.
 26. Thesystem of claim 24, further comprising a scanning controller forcontrolling said imaging device to scan an imaging region over saidfloor track.
 27. The system of claim 26, wherein said imaging device isrotatable about an axis perpendicular to said floor track, and isfurther rotatable about an axis parallel to said floor track.
 28. Thesystem of claim 24, wherein said floor mounted track comprises an outerhousing and wherein said imaging device is sealed within said outerhousing.
 29. The system of claim 24, wherein said floor mounted track islocated on a platform of a mobile unit.
 30. The system of claim 23,wherein said sensing device is a trace sensing device for detection oftraces of a predetermined chemical substance.
 31. A method of scanning alimited access space of a set of differently configured spaces, themethod comprising: interpolating a linear track into said space, saidlinear track having a sensing device movably mounted thereon, recordinga scanning program, thereby to provide specific scanning programs foreach member of said set, and controlling said sensing device to moveaccording to said recorded scanning program, thereby to scan said space,wherein said recorded scanning program comprises instructions for movingsaid sensing device linearly along said track, instructions for rotatingsaid sensing device about an axis perpendicular to said track, andinstructions for rotating said sensing device about an axis parallel tosaid track, thereby to provide a scan which is specific to said space.32. The method of claim 31, wherein said interpolating said linear trackinto said space comprises locating a vehicle over said track, anunderside of said vehicle forming said limited access space.
 33. Themethod of claim 32, wherein said linear track is flush with a floor. 34.The method of claim 31, further comprising interpolating an illuminationsource into said space.
 35. A limited access space inspection system forinspecting members of a set of defined limited access spaces,comprising: a non-optical sensing device for non-optically sensing overa region in said limited access space, a mounting for mounting saidsensing device to be scannable about said limited access space, and ascanning control unit, associated with said sensing device, andconfigured for controlling said sensing device to scan about saidlimited access space according to a pre-recorded program, said programbeing adapted for said member and comprising instructions for movingsaid sensing device linearly along a track, for rotating said sensingdevice about an axis perpendicular to said track, and for rotating saidsensing device about an axis parallel to said track, thereby to providea scan specific for said member.